1. Field of the Invention
The present invention relates to a disk-loading roller for conveying a disk such as an optical disk or a magneto-optical disk (e.g., a CD, an LD, or a DVD) into a device such as an acoustic device, an information device, or an image-viewing device for operating the disk, and more particularly, to such a disk-loading roller which prevents loading or ejecting failure which would otherwise be caused by dust deposited on the disk; in particular, sand dust or similar dust, resulting in slipping of the roller.
2. Background Art
Conventionally, devices for operating an optical disk, a magneto-optical disk, or a like disk (e.g., a CD, an LD, or a DVD) employ a pair of loading rollers disposed opposite each other so as to hold the disk on a turntable in the devices. For example, as shown in FIG. 25, loading rollers 1 are disposed such that a shaft 2 penetrates each loading roller 1 at about the center axis thereof. A pair of the rollers are disposed opposite each other, and either of the rollers is rotatably driven. The diameter of each loading roller 1 is gradually decreased from the outer end to the center along the axis, and a disk 3 loaded to a device is supported only at a peripheral portion of the disk by the loading rollers 1 for centering.
When the disk 3 is inserted between such a pair of loading rollers 1 and either of the loading rollers is rotated, the disk 3 is conveyed into the device while being in contact with the two loading rollers 1. Then, when the head of the disk 3 abuts the wall of the disk-holder, transfer of the disk 3 and rotation of the loading rollers 1 are stopped, and only the shaft 2 is self-rotated. Thus, the disk 3 is held on the turntable.
Instead of employing a pair of loading rollers 1, as shown in FIG. 26, there may be employed another mechanism such that a disk 3 is inserted between a resin sheet material 4 and a single similar loading roller 1.
However, the aforementioned loading rollers have a drawback in that the rollers cannot provide sufficient torque for conveying a disk, because of dust deposited on a disk, in particular, sand dust or the like, which has been transferred to a roller surface and deposited on the roller surface in the course of long-term use.
As disclosed in Japanese Patent No. 3627866 (in Claims and other sections), the present inventor previously proposed a loading roller having a raised/dented outer surface provided during the molding process, the outer surface having a ten-point mean roughness Rz of 0.5 to 10 μm and a mean Sm of 15 μm or less.
The disk-loading roller exhibits excellent roller performance over a long period of time, in the case where a relatively small amount of dust is present. However, when the roller is employed in the presence of a large amount of dust, or over a very long period of time, further enhancement in currently attained performance is envisaged.